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1.
Clin Radiol ; 79(4): e491-e499, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38238146

RESUMO

AIM: To develop a radiomics signature applied to magnetic resonance imaging (MRI)-images to predict cytogenetic abnormalities in multiple myeloma (MM). MATERIALS AND METHODS: Patients with newly diagnosed MM were enrolled retrospectively from March 2019 to September 2022. They were categorised into the high-risk cytogenetics (HRC) group and standard-risk cytogenetics (SRC) group. The patients were allocated randomly at a ratio of 7:3 into training and validation cohorts. Volumes of interest (VOI) was drawn manually on fat suppression T2-weighted imaging (FS-T2WI) and copied to the same location of the T1-weighted imaging (T1WI) sequence. Radiomics features were extracted from two sequences and selected by reproducibility and redundant analysis. The least absolute shrinkage selection operation (LASSO) algorithm was applied to build the radiomics signatures. The performance of the radiomics signatures to distinguish HRC with SRC was evaluated by ROC curves. The area under the curve (AUC), specificity, and sensitivity were also calculated. RESULTS: A total of 105 MM patients were enrolled in this study. The four and 11 most significant and relevant features were selected separately from T1WI and FS-T2WI sequences to build the radiomics signatures based on the training cohort. Compared to the T1WI sequence, the radiomics signature based on the FS-T2WI sequence achieved better performance with AUCs of 0.896 and 0.729 in the training and validation cohorts respectively. A sensitivity of 0.833, specificity of 0.667, and Youden index of 0.500 were achieved for the FS-T2WI radiomics signature in the validation cohort. CONCLUSIONS: The radiomics signature based on MRI provides a non-invasive and convenient tool to predict cytogenetic abnormalities in MM patients.


Assuntos
Medula Óssea , Mieloma Múltiplo , Humanos , Medula Óssea/diagnóstico por imagem , Aberrações Cromossômicas , Imageamento por Ressonância Magnética/métodos , Mieloma Múltiplo/diagnóstico por imagem , Mieloma Múltiplo/genética , Radiômica , Reprodutibilidade dos Testes , Estudos Retrospectivos
2.
Zhonghua Nei Ke Za Zhi ; 62(6): 688-692, 2023 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-37263952

RESUMO

Objective: To investigate the lifespan of erythrocytes in megaloblastic anemia (MA) patients. Methods: A prospective cohort study analysis. Clinical data from 42 MA patients who were newly diagnosed at the Department of Hematology, Lanzhou University Second Hospital from January 2021 to August 2021 were analyzed, as were control data from 24 healthy volunteers acquired during the same period. The carbon monoxide breath test was used to measure erythrocyte lifespan, and correlations between erythrocyte lifespan and laboratory test indexes before and after treatment were calculated. Statistical analysis included the t-test and Pearson correlation. Results: The mean erythrocyte lifespan in the 42 newly diagnosed MA patients was (49.05±41.60) d, which was significantly shorter than that in the healthy control group [(104.13±42.62) d; t=5.13,P=0.001]. In a vitamin B12-deficient subset of MA patients the mean erythrocyte lifespan was (30.09±15.14) d, and in a folic acid-deficient subgroup it was (72.00±51.44) d, and the difference between these two MA subsets was significant (t=3.73, P=0.001). The mean erythrocyte lifespan after MA treatment was (101.28±33.02) d, which differed significantly from that before MA treatment (t=4.72, P=0.001). In MA patients erythrocyte lifespan was positively correlated with hemoglobin concentration (r=0.373), and negatively correlated with total bilirubin level (r=-0.425), indirect bilirubin level (r=-0.431), and lactate dehydrogenase level (r=-0.504) (all P<0.05). Conclusions: Erythrocyte lifespan was shortened in MA patients, and there was a significant difference between a vitamin B12-deficient group and a folic acid-deficient group. After treatment the erythrocyte lifespan can return to normal. Erythrocyte lifespan is expected to become an informative index for the diagnosis and treatment of MA.


Assuntos
Anemia Megaloblástica , Longevidade , Humanos , Relevância Clínica , Estudos Prospectivos , Eritrócitos , Ácido Fólico , Bilirrubina , Vitaminas
3.
Antimicrob Agents Chemother ; 66(12): e0059422, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36445128

RESUMO

The intensively intermittent use of antibiotics promotes the rapid evolution of tolerance, which may lead to resistance acquisition in the following evolutionary trajectory. In addition to directly exporting antibiotics as an instant resistance strategy, efflux pumps are overexpressed in tolerant strains. To investigate how efflux pumps participate in resistance development from tolerance to resistance, we performed in vitro evolutional experiments against the antibiotic ciprofloxacin in norA efflux pump mutants of Staphylococcus aureus. These experiments demonstrated that overexpression of norA rapidly facilitated the development of ciprofloxacin resistance from tolerance to resistance through elevated spontaneous mutations. The generated resistance mutations were further fixed in the population by increasing survival ability. The observed Ser80Phe and Glu84Lys mutations in the topoisomerase IV ParC (GrlA in S. aureus) may be responsible for tolerant strains to develop resistance to ciprofloxacin since it has been reported that such mutations disrupt the water-metal ion bridge between quinolones and ParC. MepA and Sav1866 are related to the same antibiotic (ciprofloxacin) susceptibility as NorA, and they also contributed to resistance development against ciprofloxacin. MgrA positively regulated NorA expression and the development of ciprofloxacin resistance. Importantly, blocking the evolutionary pathway by coadministering ciprofloxacin with the efflux pump inhibitor reserpine effectively delayed the resistance acquisition in an in vitro experiment. This study illustrated the role of efflux pumps in the evolutionary trajectory from tolerance to resistance. The delayed resistance development caused by the efflux pump inhibitor illuminates a possible strategy for postponing the resistance acquisition from tolerance to resistance by disrupting efflux pumps.


Assuntos
Ciprofloxacina , Farmacorresistência Bacteriana , Staphylococcus aureus , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Ciprofloxacina/farmacologia , Testes de Sensibilidade Microbiana , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Farmacorresistência Bacteriana/genética
4.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(4): 779-784, 2022 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-35950408

RESUMO

Urinary system tumors affect a huge number of individuals, and are frequently recurrent and progressing following surgery, necessitating lifelong surveillance. As a result, early and precise diagnosis of urinary system cancers is important for prevention and therapy. Histopathology is now the golden stan-dard for the diagnosis, but it is invasive, time-consuming, and inconvenient for initial diagnosis and re-gular follow-up assessment. Endoscopy can directly witness the tumor's structure, but intrusive detection is likely to cause harm to the patient's organs, and it is apt to create other hazards in frequently examined patients. Imaging is a valuable non-invasive and quick assessment tool; however, it can be difficult to define the type of lesions and has limited sensitivity for early tumor detection. The conventional approaches for detecting tumors have their own set of limitations. Thus, detection methods that combine non-invasive detection, label-free detection, high sensitivity and high specificity are urgently needed to aid clinical diagnosis. Optical diagnostics and imaging are increasingly being employed in healthcare settings in a variety of sectors. Raman scattering can assess changes in molecular signatures in cancer cells or tissues based on the interaction with vibrational modes of common molecular bonds. Due to the advantages of label-free, strong chemical selectivity, and high sensitivity, Raman scattering, especially coherent Raman scattering microscopy imaging with high spatial resolution, has been widely used in biomedical research. And quantity studies have shown that it has a good application in the detection and diagnosis of bladder can-cer, renal clear cell carcinoma, prostate cancer, and other cancers. In this paper, several nonlinear imaging techniques based on Raman scattering technology are briefly described, including Raman spectroscopy, coherent anti-Stokes Raman scattering, stimulated Raman scattering, and surface-enhanced Raman spectroscopy. And we will discuss the application of these techniques for detecting urologic malignancy. Future research directions are predicted using the advantages and limitations of the aforesaid methodologies in the research. For clinical practice, Raman scattering technology is intended to enable more accurate, rapid, and non-invasive in early diagnosis, intraoperative margins, and pathological grading basis for clinical practice.


Assuntos
Análise Espectral Raman , Neoplasias Urológicas , Humanos , Masculino , Microscopia/métodos , Compostos Radiofarmacêuticos , Análise Espectral Raman/métodos , Tecnologia , Neoplasias Urológicas/diagnóstico
5.
Aust Crit Care ; 35(3): 286-293, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34176735

RESUMO

OBJECTIVE: The aim of the study was to determine the response rate to a mixed-mode survey using email compared with that to a paper survey in survivors of critical illness. DESIGN: This is a prospective randomised controlled trial. SETTING: The study was conducted at a single-centre quaternary intensive care unit (ICU) in Adelaide, Australia. PARTICIPANTS: Study participants were patients admitted to the ICU for ≥48 h and discharged from the hospital. INTERVENTIONS: The participants were randomised to receive a survey by paper (via mail) or via online (via email, or if a non-email user, via a letter with a website address). Patients who did not respond to the initial survey received a reminder paper survey after 14 days. The survey included quality of life (EuroQol-5D-5L), anxiety and depression (Hospital Anxiety and Depression Scale), and post-traumatic symptom (Impact of Event Scale-Revised) assessment. MAIN OUTCOME MEASURES: Survey response rate, extent of survey completion, clinical outcomes at different time points after discharge, and survey cost analysis were the main outcome measures. Outcomes were stratified based on follow-up time after ICU discharge (3, 6, and 12 months). RESULTS: A total of 239 patients were randomised. The response rate was similar between the groups (mixed-mode: 78% [92/118 patients] vs. paper: 80% [97/121 patients], p = 0.751) and did not differ between time points of follow-up. Incomplete surveys were more prevalent in the paper group (10% vs 18%). The median EuroQol-5D-5L index value was 0.83 [0.71-0.92]. Depressive symptoms were reported by 25% of patients (46/187), anxiety symptoms were reported by 27% (50/187), and probable post-traumatic stress disorder was reported by 14% (25/184). Patient outcomes did not differ between the groups or time points of follow-up. The cost per reply was AU$ 16.60 (mixed-mode) vs AU$ 19.78 (paper). CONCLUSION: The response rate of a mixed-mode survey is similar to that of a paper survey and may provide modest cost savings.


Assuntos
Estado Terminal , Qualidade de Vida , Humanos , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Inquéritos e Questionários
6.
Nature ; 507(7490): 90-3, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24429523

RESUMO

Forests are major components of the global carbon cycle, providing substantial feedback to atmospheric greenhouse gas concentrations. Our ability to understand and predict changes in the forest carbon cycle--particularly net primary productivity and carbon storage--increasingly relies on models that represent biological processes across several scales of biological organization, from tree leaves to forest stands. Yet, despite advances in our understanding of productivity at the scales of leaves and stands, no consensus exists about the nature of productivity at the scale of the individual tree, in part because we lack a broad empirical assessment of whether rates of absolute tree mass growth (and thus carbon accumulation) decrease, remain constant, or increase as trees increase in size and age. Here we present a global analysis of 403 tropical and temperate tree species, showing that for most species mass growth rate increases continuously with tree size. Thus, large, old trees do not act simply as senescent carbon reservoirs but actively fix large amounts of carbon compared to smaller trees; at the extreme, a single big tree can add the same amount of carbon to the forest within a year as is contained in an entire mid-sized tree. The apparent paradoxes of individual tree growth increasing with tree size despite declining leaf-level and stand-level productivity can be explained, respectively, by increases in a tree's total leaf area that outpace declines in productivity per unit of leaf area and, among other factors, age-related reductions in population density. Our results resolve conflicting assumptions about the nature of tree growth, inform efforts to undertand and model forest carbon dynamics, and have additional implications for theories of resource allocation and plant senescence.


Assuntos
Tamanho Corporal , Ciclo do Carbono , Carbono/metabolismo , Árvores/anatomia & histologia , Árvores/metabolismo , Envelhecimento/metabolismo , Biomassa , Clima , Geografia , Modelos Biológicos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Tamanho da Amostra , Especificidade da Espécie , Fatores de Tempo , Árvores/classificação , Árvores/crescimento & desenvolvimento , Clima Tropical
7.
Zhonghua Zhong Liu Za Zhi ; 42(9): 713-717, 2020 Sep 23.
Artigo em Chinês | MEDLINE | ID: mdl-32988151

RESUMO

Lung cancer is currently the malignant tumor with the highest morbidity and mortality in the world, and the main type is non-small cell lung cancer. Immune checkpoint inhibitor is a landmark discovery in the history of cancer treatment, which rewrites the history of cancer treatment, and improves the medical treatment of advanced tumors by a big step forward. The article summarizes the research progress of therapeutic drugs against anti-programmed cell death protein and programmed cell death protein ligand antibodies in the clinical diagnosis and treatment of non-small cell lung cancer. The principle of drug action, the differences in the diagnosis and treatment of non-small cell lung cancer in different clinical stages, and future research directions are discussed to provide the usage guidelines of immune checkpoint inhibitors for clinical oncologists.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Inibidores de Checkpoint Imunológico , Neoplasias Pulmonares , Antígeno B7-H1/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia , Neoplasias Pulmonares/tratamento farmacológico , Receptor de Morte Celular Programada 1/uso terapêutico
8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(9): 942-946, 2020 Sep 06.
Artigo em Chinês | MEDLINE | ID: mdl-32907282

RESUMO

Objective: Aanalysis the effect of booster one dose of hepatitis B vaccine after 21-32 years of primary immunization in Zhengding Country of Hebei Province. Methods: A total of 322 participants who were born between 1986 and 1996, received a full course of primary vaccination with plasma-derived hepatitis B vaccine (HepB), had no experience with booster vaccination, were HBsAg, anti-HBcnegative, had anti-HBs<10 mIU/ml, completed the booster and had laboratory results were enrolled between August 2017 to February 2018. A simple random method was uesd to randomly assigned 322 subjects to two groups, receiving a booster dose of HepB derived from either Saccharomyces cerevisiae ï¼»HepB (SC), (151 cases)ï¼½ or Chinese hamster ovary-derived HepB ï¼»HepB (CHO), (171 cases)ï¼½, the dose was 20 µg. Blood samples were collected 30 days after boosting and quantitatively tested for the geometric mean concentration (GMC) of anti-HBs to assess immunological effect. The related influencing factors of GMC and seroconversion rates of anti-HBs were analyzed by multiple linear regression and multivariate logistic regression models. Results: The 266 subjects (82.61%) had anti-HBs≥ 10 mIU/ml, and GMC was (131.63±12.94) mIU/ml.The seroconversion rates of anti-HBs in the anti-HBs<2.5 mIU/ml group and 2.5-10 mIU/ml group were 74.54% (161 cases) and 99.06% (105 cases), respectively (P<0.001).The seroconversion rates of anti-HBs after one dose of HepB (CHO) was higher than that of one dose of HepB (SC), the seroconversion rates were 87.13% (149 cases) and 77.48% (117 cases), respectively (P=0.023). Participants boostered with HepB (CHO) was the factor influencing the effect of strengthening immunization compared with boostered with HepB (SC), and OR (95%CI) was 1.91 (1.02-3.56) (P=0.042).Compared with anti-HBs<2.5 mIU/ml, prebooster anti-HBs was between 2.5 mIU/ml and 10 mIU/ml was the related factor of seroconversion rates of anti-HBs after booster immunization, and OR (95%CI) was 36.15 (4.91-266.02) (P<0.001). Conclusion: Participants boostered withone dose of HepB had a good immune response. Pre-booster anti-HBs concentration and a variety of vaccine were related factors of immune response.


Assuntos
Vacinas contra Hepatite B , Hepatite B/prevenção & controle , Animais , Células CHO , Cricetinae , Cricetulus , Seguimentos , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Imunização Secundária , Vacinação
9.
Opt Express ; 27(2): 470-482, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30696132

RESUMO

Molecular emission can be used for isotopic analysis in laser-induced breakdown spectroscopy (LIBS) due to its large isotopic shift. However, spectral weakness and interference have become the main flaws in molecular isotopic analysis, causing deterioration of quantitative accuracy and sensitivity. Here, to overcome these problems, laser-induced radical fluorescence (LIRF) was applied to enhance the molecular spectra and eliminate the spectral interference. The root mean square errors of cross validation (RMSECVs) of boron and carbon isotopes (11BO, 10BO, 12CN, and 13CN) improved to 2.632, 5.721, 5.990, and 1.543 at.%, as compared with 16.96, 35.79, 57.10, and 13.89 at.%, respectively, obtained in the case without LIRF. The limits of detection (LoDs) of 11BO, 10BO, 12CN, and 13CN were 0.9858, 0.8470, 1.606, and 1.193 at.%, respectively. This work demonstrates the feasibility of LIBS-LIRF to achieve isotopic determination with high accuracy and sensitivity.

10.
Opt Express ; 26(18): 22926-22933, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184949

RESUMO

The calibration-free laser-induced breakdown spectroscopy (CF-LIBS) and its variations are low cost, short time consumption, and high adaptability. However, seeking a more flexible and simple quantitative analysis method remains a challenge. A one-point and multi-line calibration (OP-MLC) was presented as a simple quantitative analysis method of LIBS. The results showed that OP-MLC-LIBS method can achieve quantitative analysis using only one standard sample, and the average relative errors (AREs) are 9, 22, 21 and 36% for Mn, Cr, Ni and Ti elements in six tested low-alloy steel samples, respectively. The method requires neither a large number of standard samples nor complicated calculations, which provides a flexible and low-cost quantitative analysis approach for development and application of LIBS.

11.
Opt Express ; 26(3): 2634-2642, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29401800

RESUMO

Boron is an essential element for industry, but it is hard to accurately and rapidly determine high boron content with conventional laser-induced breakdown spectroscopy (LIBS), due to the matrix and self-absorption effect. Using molecular emission is an alternative method for boron content analysis, but its weak spectra are major challenges. Here, boron monoxide (BO) radicals were used to establish calibration assisted by LIBS and laser-induced radical fluorescence (LIBS-LIRF). Two types of BO radical excitations, vibrational ground state excitation (LIRFG) and vibrational excited state excitation (LIRFE), were compared. The results showed that LIRFG achieved better sensitivity with a limit of detection of 0.0993 wt.%, while the LIRFE was more accurate with a root mean square error of cross validation of 0.2514 wt.%. In conclusion, this work provided a potential approach for molecular emission analysis with LIBS-LIRF.

12.
J Vet Pharmacol Ther ; 41(1): 142-147, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28730638

RESUMO

Quinocetone (QCT), an antimicrobial growth promoter, is widely used in food-producing animals. However, information about pharmacokinetics (PK) of QCT in ducks still remains unavailable up to now. In this study, QCT and its major metabolites (1-desoxyquinocetone, di-desoxyquinocetone and 3-methyl-quinoxaline-2-carboxylic) in ducks were studied using a simple and sensitive UHPLC-MS/MS assay. Twenty ducks were divided into two groups. (n = 10/group). One group received QCT by oral administration at dose of 40 mg/kg while another group received QCT intravenously at 10 mg/kg. Plasma samples were collected at various time points from 0 to 96 hr. QCT and its major metabolites in duck plasma samples were extracted by 1 ml acetonitrile and detected by UHPLC-MS/MS, with the gradient mobile phase that consisted of 0.1% formic acid in water (A) and acetonitrile (B). A noncompartment analysis was used to calculate the PK parameters. The results showed that following oral dosing, the peak plasma concentration (Cmax ) of QCT was 32.14 ng/ml and the area under the curve (AUCINF_obs) was 233.63 (h ng)/ ml. Following intravenous dosing, the Cmax , AUCINF_obs and Vss_obs were 96.70 ng/ml, 152.34 (h ng)/ ml and 807.00 L/kg, respectively. These data indicated that the QCT was less absorbed in vivo following oral administration, with low bioavailability (38.43%). QCT and its major metabolites such as 1-desoxyquinocetone and 3-methyl-quinoxaline-2-carboxylic were detected at individual time points in individual ducks, while the di-desoxyquinocetone was not detected in all time points in all ducks. This study enriches basic scientific data about pharmacokinetics of QCT in ducks after oral and intravenous administration and will be beneficial for clinical application in ducks.


Assuntos
Anti-Infecciosos/farmacocinética , Quinoxalinas/farmacocinética , Administração Oral , Animais , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/sangue , Patos , Feminino , Injeções Intravenosas , Masculino , Quinoxalinas/administração & dosagem , Quinoxalinas/sangue
13.
Cell Mol Biol (Noisy-le-grand) ; 63(7): 31-34, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28838336

RESUMO

To investigate the effects and their possible mechanisms of cell division cycle 42 (Cdc42) to neonatal rat myocardial cells subjected to the ischemia-repefusion. Neonatal rat cardiomyocytes were cultured and then subjected to the ischemia-reperfusion. Experimental groups 1. Control group; 2. Ischemia-repefusion group (I/R group); 3. Oligofectamine group (Oli group); 4. Oligofectamine and antisense oligodeoxynucleotide (AS-ODN) group (As group); 5. Oligofectamine and missense oligodeoxynucleotide (MS-ODN) group (Ms group); 6. SP600125 and Oligofectamine and AS-ODN group (SP600125/As group); 7. SP600125 and Oligofectamine and MS-ODN group (SP600125/Ms group). The cardiacmyocyte apoptosis rate was detected by AnnexinV/PI with flow cytometry. Cdc42, JNK, p-JNK, Bax and Bcl-2 were detected by western blot. In comparison with control group, Cdc42, the cardiacmyocyte apoptosis rate and phosphorylation of JNK were increased and the ratio of Bcl-2/Bax was reduced in the I/R group; Cdc42, the cardiacmyocyte apoptosis rate and phosphorylation of JNK in As group was lower than the I/R group, Oli group and the Ms group, and the ratio of Bcl-2/Bax was the highest in the four groups; Cdc42, cardiacmyocyte apoptosis rate, phosphorylation of JNK and the ratio of Bcl-2/Bax showed no differences in the I/R group, Oli group and the Ms group. Compared with As group, phosphorylation of JNK was lower in the SP600125/As group, phosphorylation of JNK in SP600125/Ms group was lower than the Ms group, and it showed no differences between the SP600125 & As group and the SP600125 & Ms group. Cdc42 in myocardial I/R can promote cardiacmyocyte apoptosis rate. AS-ODN of Cdc42 can decrease the cardiacmyocyte apoptosis rate in I/R. Cdc42 may played a role in myocardial I/R via JNK , Bcl-2 and Bax signal pathway.


Assuntos
Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Proteína cdc42 de Ligação ao GTP/metabolismo , Animais , Animais Recém-Nascidos , Antracenos/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Citometria de Fluxo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Ratos Sprague-Dawley , Fatores de Tempo , Transfecção , Proteína X Associada a bcl-2/metabolismo
14.
Int J Obes (Lond) ; 40(6): 921-8, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26984418

RESUMO

BACKGROUND/OBJECTIVE: Obesity and metabolic diseases are at an alarming level globally and increasingly affect children and adolescents. Gastric bypass and other bariatric surgeries have proven remarkably successful and are increasingly performed worldwide. Reduced desire to eat and changes in eating behavior and food choice account for most of the initial weight loss and diabetes remission after surgery, but the underlying mechanisms of altered gut-brain communication are unknown. SUBJECTS/METHODS: To explore the potential involvement of a powerful brainstem anorexia pathway centered around the lateral parabrachial nucleus (lPBN), we measured meal-induced neuronal activation by means of c-Fos immunohistochemistry in a new high-fat diet-induced obese mouse model of Roux-en-Y gastric bypass (RYGB) at 10 and 40 days after RYGB or sham surgery. RESULTS: Voluntary ingestion of a meal 10 days after RYGB, but not after sham surgery, strongly and selectively activates calcitonin gene-related peptide neurons in the external lPBN as well as neurons in the nucleus tractus solitarius, area postrema and medial amygdala. At 40 days after surgery, meal-induced activation in all these areas was greatly diminished and did not reach statistical significance. CONCLUSIONS: The neural activation pattern and dynamics suggest a role of the brainstem anorexia pathway in the early effects of RYGB on meal size and food intake that may lead to adaptive neural and behavioral changes involved in the control of food intake and body weight at a lower level. However, selective inhibition of this pathway will be required for a more causal implication.


Assuntos
Anorexia/fisiopatologia , Modelos Animais de Doenças , Ingestão de Alimentos , Comportamento Alimentar , Derivação Gástrica , Núcleos Parabraquiais/fisiopatologia , Animais , Dieta Hiperlipídica , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/patologia , Obesidade/cirurgia , Resposta de Saciedade
15.
Opt Express ; 24(23): 26521-26528, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27857385

RESUMO

The self-absorption at reduced air pressure for quantitative analysis of Mn and Cu elements in steel using laser-induced breakdown spectroscopy was investigated. The calibration curves of Mn and Cu elements at the air pressures of 100, 80, 50, 20, and 1 kPa were studied. The results show that, the nonlinearity of calibration curves which caused by self-absorption effects at atmosphere could be significantly improved by reducing the air pressure to 1 kPa, and the coefficients of determination (R2) of linear calibration curves of Mn and Cu lines are all higher than 0.99. The further study explored that the reason for the improvement was that the induced plasma became low density and the self-absorption coefficient was close to 1 when the air pressure reduced to 1 kPa.

16.
Opt Express ; 24(3): 2607-18, 2016 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-26906833

RESUMO

The matrix effect of powder samples, especially for soil samples, is significant in laser-induced breakdown spectroscopy (LIBS), which affects the prediction accuracy of the element concentration. In order to reduce this effect of the soil samples in LIBS, the standard addition method (SAM) based on background removal by wavelet transform algorithm was investigated in this work. Five different kinds of certified reference soil samples (lead (Pb) concentrations were 110, 283, 552, 675, and 1141 ppm, respectively) were used to examine the accuracy of this method. The root mean square error of prediction (RMSEP) was more than 303 ppm by using the conventional calibration method. After adoption of SAM with background removal by wavelet transform algorithm, the RMSEP was reduced to 25.7 ppm. Therefore, the accuracy of the Pb element was improved significantly. The mechanism of background removal by wavelet transform algorithm based on SAM is discussed. Further study demonstrated that this method can also improve the predicted accuracy of the Cd element.


Assuntos
Lasers , Solo/química , Análise Espectral/métodos , Algoritmos , Cádmio/análise , Calibragem , Análise de Ondaletas
17.
Opt Express ; 24(12): 13410-7, 2016 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-27410358

RESUMO

In this study, chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy (CR-SENLIBS) was for the first time applied to improve the detection sensitivities of trace heavy metal elements in aqueous solutions. Utilizing chemical replacement effect, heavy metal ions in aqueous solution were enriched on the magnesium alloy surface as a solid replacement layer through reacting with the high chemical activity metallic magnesium (Mg) within 1 minute. Unitary and mixed solutions with Cu, Pb, Cd, and Cr elements were prepared to construct calibration curves, respectively. The CR-SENLIBS showed a much better detection sensitivity and accuracy for both unitary and mixed solutions. The coefficients of determination R2 of the calibration curves were above 0.96, and the LoDs were of the same order of magnitude, i.e., in the range of 0.016-0.386 µg/mL for the unitary solution, and in the range of 0.025-0.420 µg/mL for the mixed solution. These results show that CR-SENLIBS is a feasible method for improving the detection sensitivity of trace element in liquid sample, which definitely provides a way for wider application of LIBS in water quality monitoring.

19.
Eur J Neurol ; 23(3): 597-604, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26589370

RESUMO

BACKGROUND AND PURPOSE: Haemorrhagic transformation (HT) is common after acute ischaemic stroke. Whether liver function plays a role in HT remains an open question. METHODS: Acute ischaemic stroke patients within 7 days from stroke onset were included. Baseline data including liver function tests were collected. An independent association between liver function and HT was identified by multivariate regression analysis for stroke overall and stroke subtypes. RESULTS: A total of 2788 patients were included. HT occurred in 277 patients (9.9%), with 32 patients (1.1%) with symptomatic HT and 245 patients (8.8%) with asymptomatic HT. On multivariate regression analysis, aspartate aminotransferase (AST) and bilirubin (BILI) were independently associated with HT for stroke overall. In different stroke subtypes, AST was independently associated with HT for cardioembolic stroke, BILI for stroke of undetermined aetiology, and no liver function indicators for stroke of large-artery atherosclerosis and small-artery occlusion. CONCLUSIONS: Liver function played an uneven role in HT for different stroke subtypes. Indicators of liver function independently associated with HT were AST for cardioembolic stroke, BILI for stroke of undetermined aetiology and none for stroke of large-artery atherosclerosis and small-artery occlusion.


Assuntos
Isquemia Encefálica/complicações , Hepatopatias/etiologia , Acidente Vascular Cerebral/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Hemorragia Cerebral/complicações , Feminino , Humanos , Hepatopatias/diagnóstico , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Genet Mol Res ; 15(4)2016 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-27808354

RESUMO

The objective of this study was to investigate the effect of sodium acetate on the viability of the human gastric adenocarcinoma (AGS) epithelial cell line. AGS cells were exposed to a range of concentrations of sodium acetate for different periods of time, and the sodium acetate-induced cytotoxic effects, including cell viability, DNA fragmentation, apoptotic gene expression, and caspase activity, were assessed. The changes in these phenotypes were quantified by performing a lactate dehydrogenase cell viability assay, annexin V staining, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), and several caspase activity assays. In vitro studies demonstrated that the cytotoxicity of sodium acetate on the AGS cell line were dose- and time-dependent manners. No differences were found between the negative control and sodium acetate-treated cells stained with annexin V and subjected to the TUNEL assay. However, caspase-3 activity was increased in AGS cells exposed to sodium acetate. Overall, it was concluded that sodium acetate exerted an apoptotic effect in AGS cells via a caspase-dependent apoptotic pathway.


Assuntos
Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Células Epiteliais/patologia , Acetato de Sódio/farmacologia , Neoplasias Gástricas/patologia , Adenocarcinoma/enzimologia , Caspases/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/enzimologia , Histonas/metabolismo , Humanos , Neoplasias Gástricas/enzimologia
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